import turtle

colors = ['red', 'orange', 'yellow', 'green', 'cyan', 'blue', 'purple']
turtle.pensize(20)
turtle.left(90)
for i in range(len(colors)):
    turtle.up()
    turtle.goto(150-i*20, 0)
    turtle.down()
    turtle.pencolor(colors[i])
    turtle.circle(150-i*20, 180)
    turtle.left(180)

turtle.done()